Introduction

Acute humanitarian crises pose complex ethical dilemmas for policy-makers, particularly in settings with inadequate health-care services, which often become dependent on external agencies for urgently needed care.1 These ethical dilemmas are inherent in many spheres of the response activity, including measures to mitigate infectious disease transmission, which often cause outbreaks during humanitarian crises. In the initial emergency response, interventions to reduce communicable disease transmission, such as vaccination, should be deployed along with food, water and shelter, since communicable diseases, including some that are vaccine-preventable, can spread faster and be unusually severe in the crowded, unhygienic conditions that prevail during crises. Measles, with a case-fatality rate as high as 30% during a humanitarian crisis, is a fitting example.2

Several factors need to be considered before a vaccine is deployed: the potential burden of disease; vaccine-related risks (usually minimal); the desirability of prevention as opposed to treatment; the duration of the protection conferred; cost; herd immunity in addition to individual protection; and the logistical feasibility of a large-scale vaccination programme. Vaccination may be the only practical way to protect people against certain diseases, such as meningococcal meningitis and measles. Individuals who undergo medical or surgical treatment often need ongoing care; those who get vaccinated do not, yet they receive long-lasting benefits. However, the feasibility of a mass vaccination effort depends largely on available resources.

In a recent study on ethics in humanitarian health care, respondents pointed out the need for ethical guidance on issues such as vaccination during emergency situations.3 The World Health Organization (WHO) and several humanitarian nongovernmental organizations have acknowledged this need and, in an effort to address it, WHO’s Strategic Advisory Group of Experts (SAGE) on Immunization developed a framework for decision-makers on the deployment and effective use of vaccines that can save lives during emergencies.4,5 Under the framework, countries facing crises first assess the epidemiological risk posed by a potentially dangerous vaccine-preventable disease. They then explore the feasibility of a mass vaccination campaign in light of the properties of the necessary vaccine (Fig. 1).

The conflict between individual good and the common good is at the core of the ethical issues explored in this paper – issues pertaining to the allocation of a limited vaccine supply, the balance between benefits and harms, obtaining informed consent and research conduct. The key ethical principles that should prevail during public health emergencies are rooted in the more general ethical principles governing clinical medicine and public health. Acute humanitarian emergencies differ widely in nature, in the threats they pose, in the background conditions in which they occur, and in the type of agencies that must respond. Hence, this paper does not seek to provide specific, prescriptive guidance, but merely highlights the ethical issues that policy-makers need to consider when deciding to conduct mass vaccination during any emergency response.

Beneficence and human rights

The international community and national governments have a collective duty of care to ensure that effective, affordable measures for preventing unnecessary illness and death are available to those most in need. During humanitarian emergencies, the risk of communicable disease transmission is higher than usual. According to the duty of care based on the principle of beneficence, governments must make vaccines available against the most contagious diseases. In addition to the duty of care, institutions and individuals must abide by the rule of rescue, which is “the imperative […] to rescue identifiable individuals facing avoidable death”.6,7 This is influenced by the urgency of the situation, the consequences of doing nothing, the feasibility of preventing serious consequences and the sacrifice required of the responding individual or agency.8 Humanitarian emergencies occur often enough for timely access to an assured supply of vaccine to be necessary, since certain vaccine-preventable diseases have serious outcomes, including death.9,10 Global and local communities, including governments and nongovernmental organizations, are morally obligated to ensure this supply.

Some oppose vaccination and other measures that are not routinely offered in non-crisis settings. The underlying concern, based on the doctrines of developmental relief and sustainability, is that introducing such measures will result in aid dependency. However, the argument becomes invalid if vaccination during an acute humanitarian crisis can provide immediate protection against serious illness or death.11 A higher standard of care is needed during public health crises because of the immediate threat to life. It is ethically reasonable for the standard of preventive care to revert to pre-existing levels after the heightened threat has subsided. After an acute emergency, some medical interventions call for ongoing care or rehabilitation. Vaccination does not, yet it provides long-lasting benefits.

Humanitarian assistance has traditionally been seen as charity, in keeping with the principle of beneficence, but owing to the growing human rights focus, it has come to be viewed as an obligation. Those who are able to help are obligated to ensure that the rights of affected individuals and populations are respected and promoted.12 The Sphere Project’s Humanitarian Charter “defines the legal responsibilities of states and parties to guarantee the right to assistance and protection”.13 The charter draws on the Universal Declaration of Human Rights, international humanitarian law (the Geneva Conventions) and the Convention relating to the Status of Refugees to establish a legal framework for humanitarian action.14

From a human rights perspective, vaccination equitably promotes and protects public health. Article 25 of the Universal Declaration of Human Rights states that:

“Everyone has the right to a standard of living adequate for the health and well-being of himself and his family, including food, clothing, and medical care ... [and that] every individual and every organ of society …shall strive … by progressive measures, national and international, to secure [its] universal and effective recognition.”15

“Everyone has the right to a standard of living adequate for the health and well-being of himself and his family, including food, clothing, and medical care ... [and that] every individual and every organ of society …shall strive … by progressive measures, national and international, to secure [its] universal and effective recognition.”15

Irrespective of the principles underlying humanitarian assistance, vaccine donations can ensure timely access to vaccines during emergencies. Although WHO and the United Nations Children’s Fund (UNICEF) have agreed on five requirements for “good donations practice” – i.e. suitability, sustainability, informed key persons, supply and licensing – they acknowledge that in exceptional circumstances, including emergencies, these requirements can be overlooked.16

Non-maleficence

All decisions made during humanitarian crises involve seeking a balance between beneficence (doing good) and non-maleficence (avoiding or minimizing harm). Only vaccines that have proved effective and safe in routine use are likely to be considered for mass administration during the acute phase of a humanitarian crisis. Such vaccines not only protect people against specific diseases; when administered on a large scale, they confer additional benefit through herd immunity, which reduces disease transmission above specific vaccination coverage thresholds.

Vaccines are generally administered before people are exposed to the pathogen causing the targeted disease. Unnecessary vaccination entails opportunity costs and puts people at risk of side-effects. The risk of contagion must justify vaccination. Four variables determine risk magnitude: the nature of the illness and attendant local epidemiological and environmental characteristics; the probability of transmission; disease severity and disease duration.17 If a disaster occurs where vaccination coverage is already high or the risk of an outbreak is low, additional, emergency vaccination may be of minimal benefit. For example, following the earthquake in Sichuan Province in China in 2008, mass measles vaccination would have been inappropriate because a province-wide measles vaccination campaign with high coverage had just been completed.18

Vaccines produce benefits but can also cause individual or social harm. Side-effects are an example of individual harm. These range from mild, common reactions, such as inflammation and pain at the injection site, to more severe but extremely rare events. Established vaccines, which are normally used during humanitarian emergencies, have well-known side-effect profiles, but much less is known about adverse events that can occur in ill or malnourished people during a humanitarian emergency.19 Children in this category tend to be biologically more susceptible to vaccine-preventable diseases than others, and when their parents refuse to have them vaccinated, they may be causing them individual harm. On the other hand, vaccination is sometimes contraindicated or inappropriate. A child, for instance, can be too young to receive a certain vaccine.

Parents’ refusal to get vaccinated or to vaccinate their children can cause collective harm by incrementing the pool of unprotected, susceptible individuals in a community. With herd immunity compromised, devastating disease outbreaks can occur. In these settings, individuals are morally obligated to accept vaccination to prevent harm to others.20 Harm may result from errors of omission or commission. Failure to provide a vaccine that is indicated in a specific humanitarian emergency violates the principle of non-maleficence because it places vulnerable populations and individuals at risk of contracting a vaccine-preventable disease.

Distributive justice

Distributive justice requires the fair allocation of scarce basic resources, such as shelter, food, potable water and vaccines in short supply. A small supply of vaccine could be equitably distributed through a lottery, but prioritizing particularly susceptible groups and individuals, or those most likely to spread the disease, would not be possible. Different rules govern decision-making and priority-setting during acute crises. Resource distribution during a crisis is often suboptimal because those engaged in humanitarian assistance can only do the “best they can” in the context of imperfect information, exceptional circumstances and needs far outweighing the available resources.9

When resources, especially staff, are scarce, decision-makers often choose among interventions – implicitly or explicitly – on the basis of cost-effectiveness because they are seeking to maximize benefits. Vaccination is highly cost-effective and, in emergencies, it can mitigate the risk of serious infectious disease. Furthermore, large numbers of people can be vaccinated quickly. Other factors to consider are how urgent and intense is the need for vaccination; how much faster can vaccination be delivered than other interventions; and how groups at high risk or with high transmission rates can be targeted in situations where other interventions, such as safe water and sanitation, cannot be rapidly deployed.

All countries, regardless of their socioeconomic status or experience with humanitarian emergencies, need to decide how to allocate resources. All societies have a shared vulnerability to emergencies, although poor societies are more severely devastated because poverty undermines resilience. When allocating resources, a balance must be sought between utility – maximizing the common good and ensuring smooth economic and social functioning – and equality and fairness. This balance is essential to garner people’s trust in vaccination programmes during crises. In keeping with egalitarian considerations, resource allocation should not be discriminatory; everyone should have a fair chance of being vaccinated.21 Furthermore, resources should be allocated with the aim of achieving “the greatest good for the greatest number”. Utility can conflict with equality or fairness. You can, for example, save the most lives or avert the most DALYs (disability affected life years) by allocating vaccines to urban rather than rural areas because urban areas have greater population density,21 but doing so systematically would be inequitable. In conflict zones, threats to the physical safety of health workers often determine which populations they can and cannot vaccinate.

Efforts to maximize utility can conflict with the egalitarian goal of helping the neediest. When limited supplies are allocated to the most vulnerable, overall health utility is sometimes suboptimal (e.g. less aggregate well-being, fewer lives saved, and/or fewer DALYs averted). From the perspective of value pluralism, balancing utility and equality should be the goal, rather than prioritizing one or the other. When it comes to vaccination, utility is fortunately often greatest when the most socially disadvantaged groups are targeted.

The fair distribution of limited vaccine supplies was an important issue during preparations for the 2009 pandemic influenza. People in certain categories were prioritized: those at greatest risk of infection (e.g. school children and health-care workers); those most likely to become severely ill if infected (e.g. immunosuppressed individuals and chronic disease patients); those most likely to spread infection (e.g. children and emergency service providers).22 During humanitarian emergencies in which populations are displaced, neighbouring communities also require attention. In most circumstances, host communities and refugees should be given access to each other’s services.23 Refugee or displaced populations should not be treated as separate from the host community, and assistance programmes, including vaccination, should support everyone in the area as a whole.24 The guiding principle should be to provide equitable access to vaccination to equalize risk. From an inclusive perspective, there is efficiency in covering two communities with all the resources available. Fair and equitable approaches result in less hostility and rivalry between the host and the displaced communities.13

From the point of view of utility and equity, in many cases children should be prioritized because they are generally more vulnerable than older people to vaccine-preventable diseases. In addition, saving a child’s life will result in a larger reduction in disease burden because more years of healthy life are lost when a child dies.21 Parents and caregivers often prioritize children’s needs over their own. However, some communities may place greater value on the social roles of the elderly and of pregnant women and may prioritize their access to health care during emergencies.

From a utilitarian perspective, protecting frontline health workers against disease will indirectly benefit the health of the community. Under the principle of reciprocity, it is fair to prioritize the vaccination of health-care workers, who are often more exposed than others to the risk of contagion, since they are committed to caring for society. In addition, because health-care workers come into contact with susceptible individuals, they have a moral obligation to get vaccinated to avoid placing patients at risk of infection.25

Procedural justice

Procedural justice requires transparent decision-making with involvement of the communities affected by the decisions.26 To ensure procedural justice, it is very useful to have guidelines or a legal framework to follow. Guidelines are especially valuable in certain situations: when large numbers of people need to be treated or protected against disease; when delayed or suboptimal measures could lead to very poor outcomes; and when inadequate management could result in high mortality or a large-scale epidemic. Although guidelines do not have mandatory status, if they are evidence-based and contextually appropriate they should be considered normative practice and a benchmark for judging the actions of health officials and practitioners.

National legal systems should guide the implementation of vaccination programmes in individual nation states, but they seldom accommodate humanitarian emergencies. When national legislative frameworks are absent or dysfunctional, international human rights law dictates a duty of care to protect people needing assistance, and in such cases implementation should follow international health guidelines. WHO Member States can legitimately follow WHO vaccination guidelines, which were developed on the strength of the evidence and which take many factors into account, including the epidemiologic and clinical features of the target disease, vaccine characteristics, costs, health system infrastructure, social impact, legal and ethical considerations, and the local context.27,28

Efforts to improve accountability during humanitarian emergencies have resulted in the Sphere Project, the Humanitarian Accountability Partnership and the Active Learning Network for Accountability and Performance in Humanitarian Action.29 All three seek to involve beneficiaries in the planning and implementation of aid programmes, establish codes of conduct for responding agencies, promote technical standards, and encourage the use of performance indicators and impact assessments.

Observing appropriate rules of conduct during humanitarian crises is often difficult.10 In certain political contexts, health-care workers may find that following guidance from their governments or humanitarian organizations is in conflict with their commitment to promote individuals’ best interests. Affected populations are often disenfranchised and unable to defend their own interests. All factors considered before the introduction of a vaccination programme should be well documented and publicly available to donors, community leaders, local staff and governments. Channels should also be established for affected communities to express their concerns directly to responding agencies.

Consent

Obtaining valid consent from individuals before a medical intervention is an obligation under the principle of respect for the autonomy of persons. In non-emergency circumstances, the consent process needs to be thorough and takes time. During emergencies, it has to be modified. If time permits, information on the risks and benefits of vaccination should be communicated to target populations in sufficient depth to allow individuals to make informed decisions, while bearing in mind that many will lack a basic understanding of germ theory and immunology. During emergencies, vaccination often takes place while people are too desperate for food and other basic necessities to recognize its importance. Furthermore, in some developing countries people defer to decision-makers at the expense of individual autonomy.

The amount of information provided to the public needs to be weighed against the risk of delaying action. However, any questions raised by the community should be thoroughly addressed. For example, vaccinators should be prepared to answer common questions about the diseases targeted, the benefits of vaccination, potential side-effects, follow-up and alternative options. They should also know where to refer undecided individuals who have other questions, although this may not always be feasible. Visual aids and other media can be used to convey important information to the public in a time-efficient manner.

Vaccination should be voluntary unless it becomes critical to “prevent a concrete and serious harm”.30 The degree of risk to communities will determine to what extent individual rights may be restricted. Where the threat of widespread, serious infectious disease is imminent, individual liberties may be justifiably curtailed.31 The Siracusa Principles endorsed by the United Nations Economic and Social Council state that: “Public health may be invoked as a ground for limiting certain rights in order to allow a State to take measures dealing with a serious threat to the health of the population or individual members of the population. These measures must be specifically aimed at preventing disease or injury or providing care for the sick and injured”.32 It may thus be permissible for those in authority to restrict individual autonomy to prevent harm to others. Although this approach has been limited to immediate or direct threat under traditional public health law, it should arguably be extended to what is “reasonably foreseeable” based on epidemiology and historical occurrence.33 If the risk to health is extremely high, individuals should not be allowed to compromise group protection and communal rights.34–36 When personal liberty is restricted to protect public health, the measures applied must be effective, the least restrictive (i.e. least liberty-infringing), proportional to the risk, equitable and non-discriminatory, minimally burdensome and in line with due process. Those whose liberty is violated should, when appropriate, be compensated, particularly if they experience vaccine-associated side-effects.37,38 In addition, individual rights should be restricted only with utmost respect for the dignity of persons.

Children are at particularly high risk of contracting communicable diseases during humanitarian crises. In most emergencies, mortality in children under the age of 5 years is generally two to three times higher than crude mortality.39 Vaccinating children could reduce mortality in all age groups because epidemics often arise and spread among children.40 Parents’ refusal to have their children vaccinated should be respected if the risk of disease is low or the disease is mild. However, if the risk of harm to the child is high, parental authority may be overruled to protect the child’s best interests.20,41 In emergency settings a parent or guardian may not be available, and health-care workers should be empowered to rapidly decide whether to vaccinate a child if done in the child and community’s best interests.

Research

Opportunities for health and health service research abound during humanitarian crises.42,43 However, in resource-limited settings, medical care and service delivery must always take precedence over research.44 In disaster settings, research is often conducted by the same people who provide aid and thus “rightly takes second place to the provision of life-saving assistance”.45 If specific personnel were assigned exclusively to research, critical human resources would not be diverted away from care.45 Nonetheless, such personnel should only be allowed to conduct research after a local research ethics committee has determined that enough care personnel are available to meet demand.46 Regional or international ethics review boards should be created in places without appropriate local expertise. In countries without functioning research governance structures, researchers must rely on international ethics review boards.

Research must be distinguished from disease and programme surveillance.47 Surveillance is essential for assessing vaccination coverage, informing programme planning, evaluating vaccine effectiveness, and monitoring safety in the population as a whole and in certain subgroups.48 Surveillance also allows the rapid detection of cases that may signal programme failure requiring remediation. Since surveillance activities have an opportunity cost, the data collected must be analysed and used to direct public health action.49

Under the principle of justice, communities where research is conducted must stand to benefit. Research protocols should be relevant, methodologically sound and explicit about the benefits and potential harms to study participants. They should also clearly explain how the findings will be delivered to study participants if they are relocated after the humanitarian crisis.50 Research should not undermine the provision of health services and should be carried to completion.

Although most non-medical research conducted during disasters is observational, it is subject to ethics review to ensure that individual and social benefits outweigh any risks. The level of review should be proportional to the risk associated with a specific intervention. An expedited review is admissible if the risk to participants is low, whereas a full committee review is warranted when the research involves a higher risk. If the research is urgent and very important, it can proceed without ethics committee approval, but retrospective review should be sought as soon as possible. Whenever the nature of the research to be conducted during a humanitarian emergency can be anticipated, a full review of the generic protocols should be planned and discussed in advance with local research ethics committees. Provision should be made for counselling or debriefing should participants find the research interviews traumatic or distressing.51

Potential research participants may have impaired ability to make decisions or provide voluntary individual informed consent following an acute humanitarian emergency, especially in “vulnerable communities”, as defined by the Joint United Nations Programme on HIV/AIDS. Empirical research in developing countries has shown that obtaining informed consent from study participants is not easy, even under non-emergency circumstances. Acute humanitarian crises add a layer of complexity, and decisional capacity must be carefully assessed.52–56 In acute crises in which medical care is needed, patients often assume that a research intervention is known to be therapeutic or effective. During the consent process, study participants need to be made aware that they are consenting to research only, not to special or additional care.

Conclusion

Ethical considerations are vital to decision-making about the deployment of vaccines in acute humanitarian emergencies. Commitment to human rights and the rule of rescue place an onus on wealthy countries to ensure that life-saving vaccines are made available to the poorer countries during crises. Justice and ethics obligate those who are better off to assist those who are worse off and to allocate resources accordingly.57 National health authorities are morally obligated to do all that they reasonably can to implement evidence-based guidelines to avert preventable harm.58

The allocation of a limited supply of vaccine calls for a fine balance between utility and equality and fairness. Accountability demands that decision-making be explicit, documented and open to public review.

In emergencies, the informed consent process may be reasonably modified to avoid delaying protection for vulnerable communities. Autonomy is not absolute. In situations that threaten the health and well-being of others, authorities may be required to mandate vaccination and intervene on behalf of minors against parental wishes. Finally, emergency health-care workers should be trained in ethics to improve their decision-making skills during acute humanitarian emergencies.59

Acknowledgements

This review was prepared by WHO’s Strategic Advisory Group of Experts (SAGE). SAGE’s careful review and recommendations on the manuscript are gratefully acknowledged.